This article shows how you can increase the admin login session lifetime in Magento 2.
Problem
When you are a developer, it is frustrating to login to admin panel every 15 minutes or 30 minutes. It would be easy to set the admin login session lifetime for a longer period of time so that we don’t have to login continuously.
Cause
By default, the Magento admin login session timeouts in every 900 seconds, i.e. 900/60 = 15 minutes. Hence, you are inactive in Magento admin, then you have to re-login after every 15 minutes.
Solution
1) From Admin Panel
You can increase the admin login session lifetime to a higher value by going to:
STORES > Settings > Configuration > ADVANCED > Admin > Security > Admin Session Lifetime (seconds)
You can set the value in seconds.
3600 = 1 hour
86400 = 1 day (24 hours)
31536000 = 1 year
2) From Command Line
Instead of the admin panel, you can also set the admin session lifetime value from the command line.
Show current set value
bin/magento config:show admin/security/session_lifetime
Set your desired value
bin/magento config:set admin/security/session_lifetime 3600
Check database table
> SELECT * FROM core_config_data WHERE path = 'admin/security/session_lifetime';
+-----------+---------+----------+---------------------------------+----------+---------------------+
| config_id | scope | scope_id | path | value | updated_at |
+-----------+---------+----------+---------------------------------+----------+---------------------+
| 6367 | default | 0 | admin/security/session_lifetime | 3600. | 2021-10-07 22:31:47 |
+-----------+---------+----------+---------------------------------+----------+---------------------+Hope this helps. Thanks.